If you search any thread here about insurance, it will point out that all you need is one broker to search all available insurance companies. At Sun 'n Fun, I was told by the AVEMCO folks that this is not true - that AVEMCO doesn't use the broker system, so if you want a separate quote, you can still get one from them.
We just went through the insurance quote for our "Fleet", and did just that - had our regular broker (Skysmith) do his normal thing, and gave AVEMCO the same information. Sky beat AVEMCO by about 30%.
Everyone's hours and situations are different, and that makes a huge difference, so I wouldn't take any numbers away from that - but if you feel you want just "one more quote" after your broker gives you a bunch, AVEMCO is an option to check.
BTW, Sky has done a great job for us! There are some really good brokers available to the RV world.